2016-03-28 04:54:53

by Daeseok Youn

[permalink] [raw]
Subject: [PATCH V2] staging: dgnc: replace dgnc_offset_table with bit shift.

the dgnc_offset_table has a same value with (1 << port).
So I tried to replace dgnc_offset_table array with 1 << port.
And also there are redundant assignments(tmp and current_port)
inside while loop for checking uart port, and remove them.

Signed-off-by: Daeseok Youn <[email protected]>
---
V2: clean up useless variables and increasing port value is just
for traversing all port with uart_poll. So It need to replace
'continue' with 'break' in switch statement and last of this function,
move onto next port.

drivers/staging/dgnc/dgnc_neo.c | 44 +++++++++++------------------------------
1 file changed, 12 insertions(+), 32 deletions(-)

diff --git a/drivers/staging/dgnc/dgnc_neo.c b/drivers/staging/dgnc/dgnc_neo.c
index d732e6e..6b57c44 100644
--- a/drivers/staging/dgnc/dgnc_neo.c
+++ b/drivers/staging/dgnc/dgnc_neo.c
@@ -77,9 +77,6 @@ struct board_ops dgnc_neo_ops = {
.send_immediate_char = neo_send_immediate_char
};

-static uint dgnc_offset_table[8] = { 0x01, 0x02, 0x04, 0x08,
- 0x10, 0x20, 0x40, 0x80 };
-
/*
* This function allows calls to ensure that all outstanding
* PCI writes have been completed, by doing a PCI read against
@@ -923,9 +920,7 @@ static irqreturn_t neo_intr(int irq, void *voidbrd)
struct dgnc_board *brd = voidbrd;
struct channel_t *ch;
int port = 0;
- int type = 0;
- int current_port;
- u32 tmp;
+ int type;
u32 uart_poll;
unsigned long flags;
unsigned long flags2;
@@ -960,29 +955,12 @@ static irqreturn_t neo_intr(int irq, void *voidbrd)

/* At this point, we have at least SOMETHING to service, dig further... */

- current_port = 0;
-
/* Loop on each port */
while ((uart_poll & 0xff) != 0) {
- tmp = uart_poll;
-
- /* Check current port to see if it has interrupt pending */
- if ((tmp & dgnc_offset_table[current_port]) != 0) {
- port = current_port;
- type = tmp >> (8 + (port * 3));
- type &= 0x7;
- } else {
- current_port++;
- continue;
- }
-
- /* Remove this port + type from uart_poll */
- uart_poll &= ~(dgnc_offset_table[port]);
+ type = uart_poll >> (8 + (port * 3));
+ type &= 0x7;

- if (!type) {
- /* If no type, just ignore it, and move onto next port */
- continue;
- }
+ uart_poll &= ~(0x01 << port);

/* Switch on type of interrupt we have */
switch (type) {
@@ -994,7 +972,7 @@ static irqreturn_t neo_intr(int irq, void *voidbrd)

/* Verify the port is in range. */
if (port >= brd->nasync)
- continue;
+ break;

ch = brd->channels[port];
neo_copy_data_from_uart_to_queue(ch);
@@ -1004,14 +982,14 @@ static irqreturn_t neo_intr(int irq, void *voidbrd)
dgnc_check_queue_flow_control(ch);
spin_unlock_irqrestore(&ch->ch_lock, flags2);

- continue;
+ break;

case UART_17158_RX_LINE_STATUS:
/*
* RXRDY and RX LINE Status (logic OR of LSR[4:1])
*/
neo_parse_lsr(brd, port);
- continue;
+ break;

case UART_17158_TXRDY:
/*
@@ -1027,14 +1005,14 @@ static irqreturn_t neo_intr(int irq, void *voidbrd)
* it should be, I was getting things like RXDY too. Weird.
*/
neo_parse_isr(brd, port);
- continue;
+ break;

case UART_17158_MSR:
/*
* MSR or flow control was seen.
*/
neo_parse_isr(brd, port);
- continue;
+ break;

default:
/*
@@ -1043,8 +1021,10 @@ static irqreturn_t neo_intr(int irq, void *voidbrd)
* these once and awhile.
* Its harmless, just ignore it and move on.
*/
- continue;
+ break;
}
+
+ port++;
}

/*
--
1.9.1